1. Field of Invention
The present invention relates to an improved hole-saw assembly and in particular, to a unique means of releasably locking a hole saw to a mandrel.
2. Background of the Invention
Hole-saws typically consist of a flat base, which provides support for a cylindrically shaped member protruding therefrom that includes cutting teeth at its circular end. The base is generally locked by a drill mandrel and includes a central bore through which a pilot drill, also locked by the mandrel, may pass.
The current applicant is the owner of various Australian and International Patent applications dealing with the quick and easy mounting and demounting of a hole-saw to a drill mandrel, and also of various connection means between a hole-saw and a mandrel. For example, International ApplicationPCT/AU02/01296 entitled ‘An improved hole-saw assembly’, the contents of which are incorporated by referenced herein, discloses the use of a hole-saw base including two shafts adapted to extend through the drill mandrel that are then locked by a locking member that moves between two positions. Typically the movement is a rotational one, the member being a rotatable annulus. Thus in one position the hole saw base is locked to the mandrel and in the other it is not, enabling the hole saw base and thus the hole saw to be easily and quickly removable from the mandrel.
Although the above hole saw assembly works well, in some instances different ways other than rotational motion of locking the hole saw to the mandrel may be preferred. Further in some instances it would be preferred if the locking mechanism was shielded to avoid contamination by dirt and other material.
It is therefore an object of the present invention to provide for a hole saw assembly including a locking means that overcomes at least some of the above-mentioned problems or provides the public with a useful alternative.